GeschWhat
2,059

GeschWhat 2,059

Rather than writing information about coprolite identification on multiple threads, I thought I would post information about coprolite identification here so it can be referenced in ID threads (I'm getting lazy, I know). I was also thinking it might be fun for others to post coprolites in their own collections so others can use them for comparison. So here we go:

IDENTIFYING COPROLITES:Not all rocks that look like poop have a fecal origin. Here are a few things to consider when trying to make this determination:

1. Location, Location, Location – If you haven’t guessed, the first and most important thing to consider is the location your rock was found. Don’t expect to find a coprolite unless you find it in geologic area/layer where other fossils are found. If you find things like bones, teeth and fish scales, or prehistoric tracks, you may just be in in luck.

2. Shape – While fecal matter can be rather freeform when exposed to the elements or when digestion issues arise, most coprolites are shaped like poo. As with modern extrusions, fossilized feces can be shaped like pellets, spirals, scrolls, logs, piles, etc.Their shape is dependent on shape of their producers intestinal and anal structure. Look for things like compaction folds and pinch marks.

3. Texture - Most coprolites are fine grained. If your specimen appears granular under magnification, it is most likely not a coprolite.There are some exceptions, such as marine creatures that feed on bottom sediments or coral. That is why knowing the location and geology of the area where it was discovered is so important.

4. Inclusions – Many times, coprolites will have visible inclusions. Things like fish scales, bone fragments, and teeth may not get fully digested, and can be visible on the surface. Some animals ingest stones for ballast or digestive purposes. These are known as gastroliths, and if present, are generally smooth.

5. Composition – Because herbivore scat tends to break a part and decompose rapidly, it rarely survives the fossilization process. So most fossil poo that is found is from carnivores. The reason for this is that their poo is usually high in calcium phosphate, the same mineral found in our bones.This mineral can appear in many forms. It can be hard and dense or soft and porous. If the potential coprolite appears soft and porous, there is a quick test that is often used in the field. If you touch to stone to the tip of your tongue and it sticks, chances are, it is high in calcium phosphate and could be a coprolite. If you are not that brave, you can also touch it with wet fingers to see if it feels sticky, but this is not nearly as fun. If the calcium phosphate takes a harder, denser form the “lick test” won’t work. In some instances, chemical analysis is required to definitively identify the mineral composition.

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MarcoSr
1,741

MarcoSr 1,741

Below is a GSA poster presentation of Eocene marine coprolites which I donated to the NMMNH&S from a Virginia site that I collected years ago, . To date I've donated over 20,000 coprolites from this site and others. I have similar marine coprolites from the Eocene of Belgium and Morocco and from a number of Cretaceous sites in the United States.

For comparison below are Oligocene terrestrial coprolites from my sons' ranch in Nebraska that I also donated to the NMMNH&S.

Note the large specimens on the top and bottom middle plates turned out to be geologic and not coprolites.

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Carl
1,096

Carl 1,096

Rather than writing information about coprolite identification on multiple threads, I thought I would post information about coprolite identification here so it can be referenced in ID threads (I'm getting lazy, I know). I was also thinking it might be fun for others to post coprolites in their own collections so others can use them for comparison. So here we go...

MarcoSr
1,741

MarcoSr 1,741

Good job helping science! Though I know this is just one of the many you’ve helped with.

Is that site still there? I know it hasn’t been open to most collectors for a few decades now, but I heard it was built over.

I solute Adrian Hunt and his crappy (in the best way) wordsmithing!

The owner of the main collecting area sold the land to a community developer years ago. A community sediment pond was built on part of the site. Houses were built on some more of the site. The remaining area was dug out years ago. I have not been able to find the bone bed layer on adjacent properties which I have owner permission to collect.

The owner of the main collecting area sold the land to a community developer years ago. A community sediment pond was built on part of the site. Houses were built on some more of the site. The remaining area was dug out years ago. I have not been able to find the bone bed layer on adjacent properties which I have owner permission to collect.

Marco Sr.

Another one bites the dust, Sadly.

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MarcoSr
1,741

MarcoSr 1,741

Bulletin 57 Vertebrate Coprolites 2012 from the New Mexico Museum of Natural History & Science contains over 40 papers about vertebrate coprolites. This bulletin is a great resource if you are interested in coprolites. The below link to Bulletin 57 allows free download and printing of all 40+ papers.

@GeschWhatand @Carl, what is the ratio to know what size is the bug that produced a coprolite ?

I don't know of any studies regarding arthropod size as compared to their poo. The best we can do is compare dropping size with those of extant species. The only bug coprolites I am somewhat familiar with are from termites. For the most part they measure approximately 0.3 mm across, and are about 0.5 mm in length. But there are variations. I have this example of petrified wood from the Aachen Formation (Cretaceous) in Aachen Germany that has multiple size coprolites in the same galleries. My best guess is that the larger coprolites are perhaps from a king or queen, and the tiny ones are from juveniles. However, there could be other species involved. Here are photos of the Aachen specimen.

For comparison below are Oligocene terrestrial coprolites from my sons' ranch in Nebraska

Very nice! A couple look like they have tiny inclusions. Do you ever run into anything that looks like these when you are out there? They are herbivore coprolites from the Oligocene (Brule Formation) that were found in Shannon County, South Dakota. They are just a couple of examples of the Science Museum of Minnesota collection and are attributed to Titanotheres.

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MarcoSr
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MarcoSr 1,741

Very nice! A couple look like they have tiny inclusions. Do you ever run into anything that looks like these when you are out there? They are herbivore coprolites from the Oligocene (Brule Formation) that were found in Shannon County, South Dakota. They are just a couple of examples of the Science Museum of Minnesota collection and are attributed to Titanotheres.

Lori

The herbivore coprolites don't fossilize very well and are pretty rare in the badlands. They must have been similar to modern cow pies. Also their thin form makes it easy for them to break apart even if they do fossilize. Their flat shape makes them really blend into the formation. I haven't seen any yet but I do look for them.